During hydrophobic interaction, the non-polar molecules come together, releasing some of the ordered water molecules in the clathrate structure and thus increasing entropy.
This is a thermodynamically favourable process (dG < 0), even though it is endothermic (dH > 0) because more hydrogen bonds are broken than are made.
#Unit 1. Molecules and their Interaction Relevant to Biology#Stablizing interactions (Van der Waals, electrostatic, hydrogen bonding, hydrophobic interaction)#Part B Pointers